Hard alloy is an alloy material made from hard compounds of refractory metals and bonded metals through powder metallurgy process. Hard alloy has a series of excellent properties such as high hardness, wear resistance, good strength and toughness, heat resistance, and corrosion resistance, especially its high hardness and wear resistance, which remain basically unchanged even at 500 ℃, and still have a high hardness at 1000 ℃. Hard alloys are widely used as tool materials, such as turning tools, milling cutters, planers, drill bits, boring cutters, etc., for cutting cast iron, non-ferrous metals, plastics, chemical fibers, graphite, glass, stone, and ordinary steel. They can also be used for cutting difficult to machine materials such as heat-resistant steel, stainless steel, high manganese steel, and tool steel.